The invention relates to a handheld laser distance measuring device with an extreme value measuring process, in particular a laser distance measuring instrument for use on construction sites.
In the construction trade, precise determination of distance with a precision of several millimeters is required in the distance range of up to several 100 m. The handheld laser distance measuring devices designed for this purpose and to which this invention relates make use of a phase delay measurement method of a modulated visible laser beam for measuring distance.
Along with direct measurement of the distance from a reference point at which the handheld laser distance measuring device is positioned, more complex measuring tasks by combined individual measurements using simple mathematical algorithms are accomplished; for example, the measurement of rectangular area or a parallelepiped room volume. In particular in the building trade, measurement of the exact position of objects in the form of pipelines or reinforcements relative to surfaces in the form of walls or ceilings is an essential fundamental measurement task.
According to DE 1 983 6812 A1, a handheld laser distance measuring device is known having automatic determination of a minimum value or maximum value of a measurement sequence by virtue of slight fluctuations or the angularity of the handheld laser distance measuring device to different measurement points along a measurement path and its display or further processing in special functions or for determining the normal distance to a plane or the diagonal distance to a corner. Measurement of the position of objects relative to surfaces is possible only indirectly by virtue of known algorithms worked out manually by the user using the results of a plurality of individual measurements, in particular by specific subtraction of two measurement results relative to different measurement points.